CN207332114U - A kind of steel tube confinement concrete-filled rectangular steel tube component of sandwich - Google Patents

Abstract

The utility model discloses a steel pipe-constrained rectangular concrete-filled steel pipe member with an interlayer, wherein the steel pipe-confined new steel pipe concrete member with an interlayer is composed of an outer steel pipe, an interlayer material and a core steel pipe concrete member, the outer steel pipe and the steel pipe concrete The sandwich material only provides lateral restraint for the core CFST; the outer steel pipe is circular, and the core CFST member is rectangular; the outer steel pipe is arranged along the surface of the core CFST member and is not connected to the core member Ends and beam-column joints are connected, the utility model can enhance the co-working performance between the core member steel pipe and the core concrete, improve the bearing capacity and ductility of the member, improve the failure mode of the member, and enhance the earthquake resistance, corrosion resistance and anti-corrosion of the member. fire performance; the utility model has clear principles, superior mechanical properties and low engineering cost.

Description

A Steel Tube Confined Rectangular Steel Tube Concrete Member with Interlayer

technical field

The utility model belongs to the field of building structural components, in particular to a steel tube-constrained rectangular steel tube concrete component with an interlayer.

Background technique

Concrete filled steel pipe refers to a composite member formed by filling concrete in steel pipes. During the stress process of concrete-filled steel tube members, the confinement effect of the steel tube on the concrete makes the concrete in a stress state of three-dimensional compression, so that the strength of the core concrete in the steel tube can be improved, and the ductility can be significantly improved; at the same time, the existence of the core concrete can avoid Or delay the local buckling of the steel pipe, so as to ensure that its material properties can be fully utilized. Compared with reinforced concrete structures, during the construction of concrete filled steel pipes, steel pipes can be used as formwork for pouring its core concrete, which can save formwork costs and speed up construction progress; compared with steel structures, the existence of core concrete makes the fire resistance of components better , saving fire retardant coatings and reducing project cost. Combining steel pipes and concrete into CFST, through the interaction between steel pipes and core concrete, not only can make up for the respective shortcomings of the two materials, but also can give full play to the advantages of both, so that the CFST structure has a series of superior mechanical properties. In recent years, the CFST structure has been favored by the engineering community due to its superior mechanical properties, and has been more and more widely used in high-rise buildings and long-span bridges.

However, there are also deficiencies in the application of concrete filled steel tube structures in practical engineering, including:

(1) Under the axial load, the steel tube and the core concrete bear the longitudinal load at the same time, so the restraint effect of the steel tube on the core concrete has not been fully exerted, especially for the steel tube high-strength concrete column, the steel tube's constraint on the core concrete The effect is not significant, and the core high-strength concrete is prone to shear crushing damage during the stress process; for square (rectangular) concrete-filled steel tube members, the restraint effect of the steel tube on the core concrete is uneven in the concrete section, and the corners of the steel tube and the middle of the section Concrete is constrained concrete, and the rigidity of the middle part of the steel plate is weak, and the steel pipe even breaks away from the internal concrete after buckling, and the concrete near the middle is unconstrained concrete. The improvement in performance is weak;

(2) Under the action of axial load, the steel pipe is generally in the stress state of longitudinal compression and transverse tension, which makes the longitudinal yield strength of the steel pipe lower than the unidirectional tensile yield strength of the steel pipe; with the increase of deformation, the steel pipe The lateral restraint effect on the core concrete gradually increases, especially when the steel pipe yields, the longitudinal stress of the steel pipe decreases gradually with the increase of its transverse stress, that is, the contribution of the steel pipe to the longitudinal bearing capacity of the member also weakens;

(3) When the CFST member encounters the impact of fortification earthquake equivalent to the seismic fortification intensity of the area, the member may be damaged, and its steel pipe may reach yield or buckle, and the member needs to be repaired and strengthened before it can continue to be used;

(4) Under the action of axial load, both the steel pipe and the core concrete are in the elastic stage at the initial stage of loading. Since the Poisson’s ratio of the steel pipe is greater than that of the core concrete, the lateral deformation of the steel pipe is larger than that of the core concrete, which leads to The phenomenon of detachment between the steel pipe and the core concrete occurs, especially for the high-strength concrete members with thin-walled steel pipes. Improper pouring and curing methods of concrete or shrinkage, creep and temperature deformation of the core concrete can lead to voids between the steel pipe and the core concrete. All of the above phenomena can affect the interaction between the steel pipe and the core concrete, so that the steel pipe can A large initial stress is generated, which affects the mechanical properties of the component;

(5) In the actual concrete-filled steel tube members, steel pipes need to undergo strict anti-corrosion treatment on a regular basis due to their poor corrosion resistance, otherwise they are prone to rust, which affects the durability and mechanical properties of the members, and limits the performance of such members in some special environments. For example, the development and application of ultra-long-span concrete-filled steel tube arch bridges in coastal areas is limited due to the poor corrosion resistance of the outer steel tubes;

(6) The steel pipe of the CFST member is in the outermost layer, and the steel pipe needs to bear the longitudinal load. Under the action of fire, the strength and elastic modulus of the steel pipe decrease sharply, thereby reducing the bearing capacity of the CFST member. Therefore, in actual engineering, In order to improve the fire resistance of concrete-filled steel pipe members, it is still necessary to spray a fire protection layer on the outer surface of the steel pipes, thereby increasing the project cost.

Therefore, it is necessary to design a new type of concrete-filled steel tube structural member, which can enhance the restraint effect of the steel tube on the core concrete, improve the bearing capacity and ductility of the member, improve the failure mode of the member, and enhance the corrosion resistance and fire resistance of the member.

Utility model content

The purpose of this utility model is to provide a steel pipe-constrained rectangular concrete-filled steel tube component with an interlayer, which aims to solve the deficiencies of the existing steel tube concrete component technology, to enhance the joint work performance between the core component steel tube and the core concrete, and to improve the structural strength of the component. Bearing capacity and ductility, improve the failure mode of components, and enhance the seismic, corrosion and fire resistance of components.

The utility model is realized in this way, a steel pipe constrained rectangular concrete-filled steel tube member with an interlayer is composed of a core assembly of a hollow cylinder structure and an outer layer assembly of a hollow cylinder structure, and the outer layer assembly and the core Interlayer materials are filled between the components; inner layer materials are filled inside the core component, and the cross-sectional figures of the core component and the outer layer component are both centrally symmetrical figures; the core component and the outer layer component are The center of symmetry of the cross-section coincides; the width of the inner wall of the outer layer component is greater than the width of the outer wall of the core component and the two do not touch each other; the length of the outer layer component is smaller than the core component; the length of the sandwich material is the same as the width of the core component The outer layer components are the same; the inner layer material length is the same as the core component. Since the length of the core component is longer than the outer component and the interlayer material, and the outer component and the interlayer material are not connected to the beam-column joints of the core component in actual engineering, the outer component in this scheme is essentially unstressed, but Provides lateral restraint to core components and concrete.

This is very different from the ordinary double-layer nested steel pipes in the prior art. Although the double-layer steel pipes in the prior art are the same as this solution in terms of the cross-sectional structure of the middle part of the member, due to its outer layer structure The length of the inner layer is the same as that of the inner layer structure, so both of them bear the longitudinal force at the same time when the force is applied.

A further technical solution of the utility model is: the outer layer component is a hollow cylinder structure. The hollow cylindrical structure can provide the same lateral restraint in all directions, thereby enhancing the restraint of the inner layer material by the core component.

A further technical solution of the utility model is: the cross-section of the core component is polygonal. Polygons can bring better forces.

A further technical solution of the utility model is: the cross-section of the core component is rectangular.

A further technical solution of the utility model is: the cross-section of the core component is square.

A further technical solution of the utility model is: the manufacturing material of the core component and the outer layer component is one of carbon steel, stainless steel and high-strength steel. These materials are readily available and inexpensive.

The further technical scheme of the utility model is: the preparation material of the inner layer material is one or more of high-performance concrete, high-strength concrete, ordinary concrete and recycled concrete; the preparation material of the interlayer material is cement-based grouting material , fiber-reinforced grouting material, structural adhesive, high-performance concrete, high-strength concrete, ordinary concrete or recycled concrete. These materials are readily available and inexpensive.

The beneficial effects of the utility model are: compared with the prior art, the utility model has the following beneficial effects:

(1) The outer round steel casing does not bear the longitudinal load, and acts as a constraint on the steel tube and core concrete of the core square (rectangular) CFST member. Compared with the traditional CFST member, the core concrete has a stronger restraint effect. Its ductility can be further improved, weakening the phenomenon of shear failure of the core concrete, and at the same time, the outer round steel casing has a restraining effect on the steel pipe (inner square (rectangular) steel pipe) of the core square (rectangular) CFST member It can effectively prevent or delay the local buckling of the inner steel pipe, while the outer round steel casing does not bear the longitudinal load, and also avoids the buckling of the steel pipe. Therefore, the utility model will effectively improve the failure mode of the traditional CFST member;

(2) The outer round steel casing plays a restraining role on the steel pipe and core concrete of the core square (rectangular) CFST column, the restraint effect on the core concrete is enhanced, and its bearing capacity can be further improved; The tensile effect will be weakened, and the longitudinal stress will be increased correspondingly, making a greater contribution to the bearing capacity of the component. Compared with the traditional steel tube concrete component, the mechanical properties of the core concrete and steel tube of the utility model can be more effectively exerted, and the force is clear and reasonable. , the bearing capacity can be significantly improved;

(3) The outer round steel casing does not bear the longitudinal load, avoiding the buckling of the steel pipe, and at the same time can more effectively restrain the core concrete, reducing the phenomenon of core concrete damage; when the component is subjected to a fortification earthquake equivalent to the seismic fortification intensity of the When impacted, damage may occur. The utility model is used to partially repair and strengthen the components, so that the components can continue to be used. Therefore, the utility model not only improves the anti-seismic ability of traditional steel pipe concrete components, but also provides a way for post-earthquake repair and reinforcement of components. ;

(4) The outer round steel casing does not bear the longitudinal load, which can weaken the disengagement phenomenon between the inner steel pipe and the core concrete at the initial stage of loading, so that the inner steel pipe can restrain the core concrete at the initial stage of loading, and enhance the mechanics of the component Performance; the utility model can also effectively overcome the problem of insufficient bonding strength between the inner steel pipe and the core concrete caused by core concrete pouring, improper maintenance methods, or core concrete shrinkage, creep, and temperature deformation, thereby improving the inner steel pipe and concrete. work performance between

(5) When the outer round steel casing of the component is made of stainless steel, the outer stainless steel tube will greatly improve the corrosion resistance of the component, reduce the anti-corrosion treatment process, and expand the traditional steel tube concrete component to wet and corrosive media. and other special environments;

(6) In this utility model, a layer of interlayer material is outsourced on the outer side of the original core square (rectangular) steel pipe concrete member. The specific heat capacity of the interlayer material is larger than that of the inner steel pipe, which can effectively delay the heat transfer of the fire. At the same time, the outer round steel The casing does not bear the longitudinal load under the action of fire, and all of the above can improve the fire resistance limit of the core square (rectangular) CFST member.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments described in this application. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is a schematic structural view of a steel pipe-constrained rectangular concrete-filled steel tube member provided by an embodiment of the utility model.

Fig. 2 is a schematic cross-sectional view of a steel tube-constrained rectangular concrete-filled steel tube member provided by an embodiment of the utility model.

Fig. 3 is a schematic diagram of the preparation process of the steel pipe-constrained rectangular concrete-filled steel tube member provided by the embodiment of the utility model.

Fig. 4 is a schematic diagram of the fixing part in the processing method of the steel pipe-constrained rectangular concrete-filled steel pipe member provided by the embodiment of the utility model.

Reference numerals: 1—inner layer material; 2—core component; 3—outer layer component; 4—interlayer material; 5—fixer.

Detailed ways

The following descriptions of the various embodiments refer to the accompanying drawings to illustrate specific embodiments in which the present invention can be implemented. The directional terms mentioned in the present invention, such as "up", "down", "front", "back", "left", "right", "inside", "outside", "side", etc., are only Refer to attached drawings for directions. Therefore, the used directional terms are used to illustrate and understand the present invention, but not to limit the present invention.

Fig. 1 is a schematic structural view of a steel pipe-constrained rectangular concrete-filled steel tube member provided by an embodiment of the utility model. It can be seen from Figure 1 that the appearance of the steel pipe-constrained rectangular concrete-filled steel tube member provided by this scheme is provided. A steel pipe-constrained rectangular concrete-filled steel tube member with an interlayer, which is composed of a core assembly 2 of a hollow cylinder structure and an outer layer assembly 3 of a hollow cylinder structure, and an interlayer is filled between the outer layer assembly and the core assembly Material 4; the inner layer material 1 is filled inside the core component, and the cross-sectional figures of the core component and the outer layer component are centrally symmetrical figures; the symmetry of the cross-section of the core component and the outer layer component The center coincides; the inner wall width of the outer layer assembly is greater than the outer wall width of the core assembly and the two do not touch each other; the length of the outer layer assembly is smaller than the core assembly; the length of the sandwich material is the same as that of the outer layer assembly Same; the inner material length is the same as the core component.

Fig. 2 is a schematic cross-sectional view of a steel tube-constrained rectangular concrete-filled steel tube member provided by an embodiment of the utility model. It can be seen from FIG. 2 that in this embodiment, the core component adopts a square structure, while the outer layer component adopts a circular structure.

Since the length of the core component is longer than that of the outer layer component, the outer layer component in this solution is essentially free of force, and only provides lateral restraint for the core component and concrete. Compared with the traditional concrete-filled steel pipe member, the utility model can enhance the co-working performance between the steel pipe and the core concrete, improve the bearing capacity and ductility of the member, improve the failure mode of the member, and enhance the earthquake resistance, corrosion resistance and fire resistance of the member.

This is very different from the ordinary double-layer nested steel pipes in the prior art. Although the double-layer steel pipes in the prior art are the same as this solution in terms of the cross-sectional structure of the middle part of the member, due to its outer layer structure The length of the inner layer structure is the same as that of the inner layer structure, so when the force is applied, the two are subjected to the longitudinal force at the same time, so that the restraint effect of the outer layer structure steel pipe on the inner layer structure cannot be fully exerted.

In this solution, when the two ends of the core component are longer than the two ends of the outer steel pipe and the sandwich material, the outer component can be completely free from longitudinal loads. In actual engineering, the outer component and the sandwich material along the The core components are generally arranged but not connected in any way to the ends and nodes of the core components.

Further, the manufacturing material of the core component and the outer layer component is one of carbon steel, stainless steel and high-strength steel, so as to meet different engineering needs, especially when the outer layer component adopts stainless steel pipe, it can improve The corrosion resistance and aesthetic effect of the overall component.

Further, the preparation material of the inner layer material is one or more of high-performance concrete, high-strength concrete, ordinary concrete and recycled concrete, so as to meet the needs of different projects. When components are used in high-rise, super high-rise buildings or large In the span arch bridge structure, high-performance concrete and high-strength concrete can exert greater advantages and benefits, and when the core concrete is recycled concrete, it can solve the problem of shortage of natural aggregate resources, protect the ecological environment of the aggregate production area, and solve urban problems. Waste stacking, land occupation and environmental pollution have significant social, economic and environmental benefits.

The preparation material of the interlayer material is one or more of cement-based grouting material, fiber-reinforced grouting material, structural glue, high-performance concrete, high-strength concrete, ordinary concrete or recycled concrete. These materials are readily available and inexpensive.

Next, the preparation method of the steel pipe-confined rectangular steel pipe concrete member with interlayer provided by this scheme is introduced. The method includes the following steps:

Step A: a positioning step, the positioning step is to position the core component and the outer layer component according to the design;

Wherein, said step A includes the following sub-steps:

Step A1: the step of making components, the step of making components is to intercept the rectangular core component and the outer layer component according to the design length, or select the plate to be crimped and welded according to the design requirements to form the circular outer layer component and the core component;

Step A2: component fixing step, inserting the fixing member 5 at the end of the core component and the outer layer component, Fig. 3 is a schematic diagram during the preparation process of the steel tube constrained rectangular steel tube concrete member with interlayer provided by the embodiment of the present utility model . The installation position of the fixing member can be seen from FIG. 3 . The fixing part is a ring-shaped steel plate, and Fig. 4 is a schematic diagram of the fixing part in the processing method of the steel pipe constrained rectangular steel tube concrete member with interlayer provided by the embodiment of the utility model. It can be seen from Figure 4 that there is a rectangular hollow in the middle of the fixing member, the shape of the hollow is the same as the outer surface of the core component, and the outer diameter of the fixing member is the same as that of the outer layer component. The fixing piece is connected with the outer layer component by spot welding. The position between the core component and the outer component is guaranteed by the fixing piece to ensure that the two can be concentric.

Step B: a pouring step, wherein the pouring step is pouring the inner layer material into the core assembly, and pouring the interlayer material into the space between the outer layer assembly and the core assembly;

The step B includes the following sub-steps:

Step B1: the pouring step of the inner layer material, the step of pouring the inner layer material is to prepare the inner layer material with concrete according to the design ratio, lay a polyethylene film on the surface of the fixing part 5 in contact with the interlayer material 4 and apply machine oil; then put The inner layer material is poured into the interior of the core component, and fully vibrated until the inner layer material is compacted;

Step B2: The interlayer material pouring step, the interlayer material pouring step is to prepare the interlayer material according to the design ratio, pour the inner layer material between the core component and the outer layer component, and fully vibrate until the The material of the inner layer is compacted.

Step C: a maintenance step, the maintenance step is to maintain the product obtained in step B.

Specifically, the step C includes the following sub-steps:

Step C1: Carry out maintenance on the poured specimen;

Step C2: Remove the fasteners used in Step A2.

Compared with the prior art, the utility model has the following beneficial effects:

(1) The outer round steel casing does not bear the longitudinal load, and acts as a constraint on the steel tube and core concrete of the core square (rectangular) CFST member. Compared with the traditional CFST member, the core concrete has a stronger restraint effect. Its ductility can be further improved, weakening the phenomenon of shear failure of the core concrete, and at the same time, the outer round steel casing has a restraining effect on the steel pipe (inner square (rectangular) steel pipe) of the core square (rectangular) CFST member It can effectively prevent or delay the local buckling of the inner steel pipe, while the outer round steel casing does not bear the longitudinal load, and also avoids the buckling of the steel pipe. Therefore, the utility model will effectively improve the failure mode of the traditional CFST member;

(2) The outer round steel casing plays a restraining role on the steel pipe and core concrete of the core square (rectangular) CFST column, the restraint effect on the core concrete is enhanced, and its bearing capacity can be further improved; The tensile effect will be weakened, and the longitudinal stress will be increased correspondingly, making a greater contribution to the bearing capacity of the component. Compared with the traditional steel tube concrete component, the mechanical properties of the core concrete and steel tube of the utility model can be more effectively exerted, and the force is clear and reasonable. , the bearing capacity can be significantly improved;

(3) The outer round steel casing does not bear the longitudinal load, avoiding the buckling of the steel pipe, and at the same time can more effectively restrain the core concrete, reducing the phenomenon of core concrete damage; when the component is subjected to a fortification earthquake equivalent to the seismic fortification intensity of the When impacted, damage may occur. The utility model is used to partially repair and strengthen the components, so that the components can continue to be used. Therefore, the utility model not only improves the anti-seismic ability of traditional steel pipe concrete components, but also provides a way for post-earthquake repair and reinforcement of components. ;

(4) The outer round steel casing does not bear the longitudinal load, which can weaken the disengagement phenomenon between the inner steel pipe and the core concrete at the initial stage of loading, so that the inner steel pipe can restrain the core concrete at the initial stage of loading, and enhance the mechanics of the component Performance; the utility model can also effectively overcome the problem of insufficient bonding strength between the inner steel pipe and the core concrete caused by core concrete pouring, improper maintenance methods, or core concrete shrinkage, creep, and temperature deformation, thereby improving the inner steel pipe and concrete. work performance between

(5) When the outer round steel casing of the component is made of stainless steel, the outer stainless steel tube will greatly improve the corrosion resistance of the component, reduce the anti-corrosion treatment process, and expand the traditional steel tube concrete component to wet and corrosive media. and other special environments;

(6) In this utility model, a layer of interlayer material is outsourced on the outer side of the original core square (rectangular) steel pipe concrete member. The specific heat capacity of the interlayer material is larger than that of the inner steel pipe, which can effectively delay the heat transfer of the fire. At the same time, the outer round steel The casing does not bear the longitudinal load under the action of fire, and all of the above can improve the fire resistance limit of the core square (rectangular) CFST member.

The above descriptions are only preferred embodiments of the present utility model, and are not intended to limit the present utility model. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present utility model shall be included in this utility model. within the scope of protection of utility models.

Claims (6)

1. A kind of 1. steel tube confinement concrete-filled rectangular steel tube component of sandwich, it is characterised in that：By the core of hollow cylinder structure The outer layer assembly nested groups of component and hollow cylinder structure are into being filled with interlayer between the outer layer assembly and the core component Material；It is filled with inner layer material inside the core component, the cross section figure of the core component and the outer layer assembly is equal Centered on symmetric figure；The symmetrical centre of the cross section of the core component and the outer layer assembly overlaps；The outer layer assembly Inner wall width be more than the core component outer wall width and both do not contact with each other；The length of the outer layer assembly is less than institute State core component；The sandwich material length is identical with the outer layer assembly；The inner layer material length and the core component It is identical.
2. 2. the steel tube confinement concrete-filled rectangular steel tube component of sandwich according to claim 1, it is characterised in that：It is described outer Layer assembly is hollow cylindrical structure.
3. 3. the steel tube confinement concrete-filled rectangular steel tube component of sandwich according to claim 1, it is characterised in that：The core The cross section of heart component is polygon.
4. 4. the steel tube confinement concrete-filled rectangular steel tube component of sandwich according to claim 3, it is characterised in that：The core The cross section of heart component is rectangle.
5. 5. the steel tube confinement concrete-filled rectangular steel tube component of sandwich according to claim 4, it is characterised in that：The core The cross section of heart component is square.
6. 6. according to the steel tube confinement concrete-filled rectangular steel tube component of any sandwich in claim 1-5, its feature exists In：The manufacture material of the core component and the outer layer assembly is one kind in carbon steel, stainless steel and high-strength steel.